Updated 1:43 pm, Tuesday, May 20, 2014

Welington Castillo's bat breaks as he doubles. The barrel - point first - struck Tyler Colvin, puncturing his lung.

Welington Castillo's bat breaks as he doubles. The barrel - point first - struck Tyler Colvin, puncturing his lung.

Photo: Alan Diaz, AP

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Tyler Colvin #21 of the Chicago Cubs holds his chest after being impaled by a bat splinter during a MLB game against the Florida Marlins at Sun Life Stadium on September 19, 2010 in Miami, Florida. The Cubs won 13-3. less

Tyler Colvin #21 of the Chicago Cubs holds his chest after being impaled by a bat splinter during a MLB game against the Florida Marlins at Sun Life Stadium on September 19, 2010 in Miami, Florida. The Cubs won ... more

Photo: Michael DeHoog/Sports Imagery, Getty Images

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Tyler Colvin #21 of the Chicago Cubs holds his chest after being impaled by a bat splinter during a MLB game against the Florida Marlins at Sun Life Stadium on September 19, 2010 in Miami, Florida. The Cubs won 13-3. less

Tyler Colvin #21 of the Chicago Cubs holds his chest after being impaled by a bat splinter during a MLB game against the Florida Marlins at Sun Life Stadium on September 19, 2010 in Miami, Florida. The ... more

Photo: Michael DeHoog/Sports Imagery, Getty Images

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Tyler Colvin was having a banner rookie year in 2010 when a piece of a broken bat punctured his lung and derailed his career. "I think everyone has ups and downs," Colvin said. "It's how you deal with them."

Tyler Colvin was having a banner rookie year in 2010 when a piece of a broken bat punctured his lung and derailed his career. "I think everyone has ups and downs," Colvin said. "It's how you deal with them."

Photo: Alan Diaz, AP

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Tyler Colvin #21 of the Chicago Cubs holds his chest after being impaled by a bat splinter during a MLB game against the Florida Marlins at Sun Life Stadium on September 19, 2010 in Miami, Florida.

Tyler Colvin #21 of the Chicago Cubs holds his chest after being impaled by a bat splinter during a MLB game against the Florida Marlins at Sun Life Stadium on September 19, 2010 in Miami, Florida.

Photo: Michael DeHoog/Sports Imagery, Getty Images

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San Francisco Giants' Tyler Colvin, right, shakes hands with third base coach Tim Flannery, left, after Colvin's solo home run against the Atlanta Braves during the second inning of a baseball game on Monday, May 12, 2014, in San Francisco. (AP Photo/Marcio Jose Sanchez) less

San Francisco Giants' Tyler Colvin, right, shakes hands with third base coach Tim Flannery, left, after Colvin's solo home run against the Atlanta Braves during the second inning of a baseball game on Monday, ... more

Photo: Marcio Jose Sanchez, Associated Press

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Chicago's Tyler Colvin, left, celebrates with Derrek Lee after hitting a solo home run off Wandy Rodriguez during the sixth inning in 2010.

Chicago's Tyler Colvin, left, celebrates with Derrek Lee after hitting a solo home run off Wandy Rodriguez during the sixth inning in 2010.

Photo: Charles Rex Arbogast, AP

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Chicago's Tyler Colvin slams down his bat after striking out in the ninth inning in 2010.

Chicago's Tyler Colvin slams down his bat after striking out in the ninth inning in 2010.

Photo: Paul Beaty, AP

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Colorado Rockies' Tyler Colvin (21) is greeted by third base coach Rich Dauer as he rounds third base after hitting a solo home run off Oakland Athletics starting pitcher Bartolo Colon during the first inning of an interleague baseball game, Tuesday, June 12, 2012, in Denver. less

Colorado Rockies' Tyler Colvin (21) is greeted by third base coach Rich Dauer as he rounds third base after hitting a solo home run off Oakland Athletics starting pitcher Bartolo Colon during the first inning ... more

Photo: Jack Dempsey, Associated Press

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Colorado Rockies Carlos Gonzalez, left, Tyler Colvin, center, and relief pitcher Matt Belisle get wet towels to cool off in the hot weather during a baseball game against the Washington Nationals, Sunday, July 8, 2012, in Washington. The Rockies won 4-3. less

Colorado Rockies Carlos Gonzalez, left, Tyler Colvin, center, and relief pitcher Matt Belisle get wet towels to cool off in the hot weather during a baseball game against the Washington Nationals, Sunday, July ... more

Tyler Colvin throws back to the infield in the ninth inning. The San Francisco Giants played the Miami Marlins at AT&T Park in San Francisco, Calif., on Sunday, May 18, 2014. The Giants won 4-1.

Tyler Colvin throws back to the infield in the ninth inning. The San Francisco Giants played the Miami Marlins at AT&T Park in San Francisco, Calif., on Sunday, May 18, 2014. The Giants won 4-1.

Photo: The Chronicle

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Tyler Colvin #10 of the San Francisco Giants is congratulated by teammates in the dugout after hitting a two-RBI triple against the Atlanta Braves during the seventh inning at AT&T Park on May 12, 2014 in San Francisco. less

Tyler Colvin #10 of the San Francisco Giants is congratulated by teammates in the dugout after hitting a two-RBI triple against the Atlanta Braves during the seventh inning at AT&T Park on May 12, ... more

Affeldt and Colvin have something in common. Each has endured an accidental and serious stabbing that has become attached to their names like the asterisk alongside Roger Maris' "61."

Affeldt has been able to laugh about the 2011 hamburger-separating disaster that severely injured his non-throwing hand, although he surely would prefer to be known more for his stellar relief work on two World Series championship teams and his crusade against human trafficking.

Similarly, Colvin would like to be remembered someday for a solid career of hitting from the left side of the plate and his defense, not as the poor sod who could have been killed by a flying spear of maple bat in a 2010 major-league game.

A doctor in Chicago drove that point home in a way Colvin cannot forget, promising to tell the outfielder how lucky he was that the bat hit him where it did, in the upper part of his left chest, just below the collarbone.

"We never really had that talk," Colvin said as he prepared for a weekend game at AT&T Park. "Just hearing that you realize, hey, an inch here, an inch there, a millimeter - who knows what it could have done?"

Colvin was a rookie with the Cubs on Sept. 19, 2010, when he was playing at Dolphins Stadium in Miami in a game for two teams daydreaming about autumn golf.

In the second inning, Marlins pitchers Andrew Miller and Brett Sinkbeil could not find the plate to save their lives. They would have walked the peanut vendors had they stepped to the plate.

Colvin drew a bases-loaded walk and had reached third when Welington Castillo took a swing that broke his bat. The ball went over third base, and Colvin remembers turning to see its path. He did not see the barrel of Castillo's bat spinning toward him.

The sharp end of the bat stabbed Colvin's chest, popped out, then hit the ground. It invaded Colvin's body long enough to puncture a hole in his skin and left lung, which deflated. Colvin knew none of that at the time. He thought he had the wind knocked out of him until the on-deck hitter, pitcher Jeff Samardzija, told Colvin he was bleeding.

Cubs trainers went into crisis mode, getting Colvin to the dugout, then the training room, and summoning paramedics. Next came a helicopter flight to a hospital, where he was treated.

"Once Tyler saw it, you could see the panic a little bit on his face," said Jeff Baker, a Marlins utilityman who was playing for the Cubs that day and scored ahead of Colvin.

"Obviously, Tyler was concerned. Everybody was concerned. It's not every day you see a guy with basically a 2- to 3-inch hole in his chest. It was tough to see him lying there on the table. We didn't know how bad it was. It was definitely scary for everybody."

Including Colvin.

"You've got a million things going through your head and you don't know how serious it is or how close you were to anything else," Colvin said. "I had all my family elsewhere. I knew they were going to be worried and I couldn't get into contact with them."

He recovered in the hospital and did not play the rest of what had been a promising season, which included 20 home runs and an .816 OPS in 395 plate appearances.

There was no reason to believe the bizarre injury would slow his big-league career, but it did. He had to delay his conditioning during the offseason until the lung was restored, but he does not blame that entirely for a big step back in 2011, when he hit .150 and got shipped to the Rockies the following offseason.

Colvin has not had the career expected of the 13th overall pick in the 2006 draft. He spent a good chunk of 2011 and 2013 in the minors before the Rockies released him.

"Not everyone's path is just right there, an easy path," Colvin said. "I think everyone has ups and downs. It's how you deal with them. I've definitely had some ups and downs. I've had some unfortunate things happen. But you learn from it all."

The Giants provided a perfect opportunity for Colvin because their organization was and is short of outfielders. After a major-league deal with the Orioles fell through over his back issues, he signed a minor-league deal with the Giants.

Back pains returned in spring training and left the Giants no choice but to keep Colvin off the Opening Day roster. His deal allowed him to declare free agency at that stage, but he decided to stay because he still sensed greater opportunity here. He went to Triple-A and earned a May 10 promotion.

Colvin gave the fans quite a jolt in his first game at AT&T Park, sending a ball into McCovey Cove for his first Giants hit. His first four hits over two games constituted a cycle: homer, triple, single, double.

Baker sees Colvin as a perfect fit with the Giants and said he was a "great rookie" in Chicago.

"The way the game is now, young guys have a lot of hype when they come up," Baker said. "Some of them come to clubhouse with egos. Tyler never had that. He was always humble."

And courageous. Colvin could have returned to the field afraid of maple bats. He is not. He even uses them at times, although his current lumber is ash.

"It really is part of the game," he said. "It's going to happen. We obviously swing at bad pitches and break our bats. You hope you can limit the ones that fly off like that."

And Major League Baseball has. Effective rules were installed to govern the quality and dimensions of maple bats in a bid to reduce those scary, dangerous splits.

The impetus was two incidents in 2008, two years before Colvin's harrowing day at Marlins Park, which could have proved a lot worse than it was.

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